Tiahuanaco, ancient native ruin, W Bolivia, 34 mi (55 km) S of Lake Titicaca, near the Peruvian border. Nearly 13,000 ft (3,962 m) above sea level, Tiahuanaco was probably the center of a pre-Inca empire and is believed by some to have been built by the Aymara. Much of the construction is unfinished. Building was begun at some time before A.D. 500, and there is evidence of additional construction (c.1100-1300). About 1000, Tiahuanaco culture spread to E Bolivia, N Chile, and Peru; the culture flourished for about 200 years. Built of massive blocks weighing up to 100 tons and brought from several miles away, the structures of Tiahuanaco are superb examples of masonry. The stones, fitted together without mortar, were cut, squared, dressed, and notched with a precision equaled in no other aboriginal South American civilization, not even the Inca. Construction is largely of the platform or monolithic type decorated by conventional incised carving or heads in low relief. The creators of Tiahuanaco also excelled at ceramics; Tiahuanaco painted pottery is one of the great achievements of pre-Columbian art.